This species resembles the northern bottlenose whale, with a bulbous melon (especially in adult males), tube-like beak, throat grooves, small dorsal fin, small blunt flippers, and flukes with no notch (or only a shallow one).
These animals are light brown to dull yellow in color. The belly and probably much of the head are lighter. Large animals can be covered with light splotches, scratches, and scars. The color pattern of young calves is unknown.
There is a single pair of conical teeth at the tip of the lower jaw, which erupts only in adult males, and is not visible outside the closed mouth. There may be a smaller second pair, and several sets of vestigial teeth, as well.
Maximum known sizes are 7.8 m for females and about 7.2 m for males. If females are, in fact, larger than males, this species differs from its northern counterpart. However, the disparity is more likely a result of the small sample size of measured animals. Length at birth appears to be around 2 m.
Can be Confused With
Southern bottlenose whales can be distinguished from Arnoux’s beaked whales by differences in dorsal fin and head shape, and from Cuvier's beaked whales and various mesoplodonts primarily by head shape and body patterning. They are most likely to be confused with Longman’s beaked whale, and detailed views of the animals may be needed to distinguish the species.
Southern bottlenose whales are thought to have a circumpolar distribution in the Southern Hemisphere, south of 30°S. They apparently migrate, and are found in Antarctic waters during the summer, where they tend to occur within about 120 km of the ice edge. Like other beaked whales, these are deep-water oceanic animals.
Ecology and Behavior
Pods of less than 10 are most common, but groups of up to 25 have been seen. They are deep divers that can remain underwater for over an hour.
There is essentially nothing known of the reproductive biology of this species.
Feeding and Prey
Southern bottlenose whales are thought to take primarily squid, but probably also eat fish and possibly some crustaceans.
Threats and Status
No significant exploitation of southern bottlenose whales is known. Currently, they are listed as ‘Lower Risk/Conservation Dependent (IUCN)’ and ‘Not Listed’ (ESA).
Dixon, J.M., L. Frigo and R.L.C. Moyle. 1994. New information on the southern bottlenose whale, Hyperoodon planifrons (Cetacea Ziphiidae), from a recent stranding in Victoria, Australia. Australian Mammalogy 17:85-95.
Gowans, S. 2002. Bottlenose whales Hyperoodon ampullatus and H. planifrons. pp. 128-129 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press.
Mead, J.G. 1989. Bottlenose whales Hyperoodon ampullatus (Forster, 1770) and Hyperoodon planifrons Flower, 1882. pp. 321-348 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 4: River dolphins and the larger toothed whales. Academic Press.